/*
 * Wrapper functions for OpenSSL libcrypto
 * Copyright (c) 2004-2015, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "includes.h"
#include <openssl/opensslv.h>
#include <openssl/err.h>
#include <openssl/des.h>
#include <openssl/aes.h>
#include <openssl/bn.h>
#include <openssl/evp.h>
#include <openssl/dh.h>
#include <openssl/hmac.h>
#include <openssl/rand.h>
#ifdef CONFIG_OPENSSL_CMAC
#include <openssl/cmac.h>
#endif							/* CONFIG_OPENSSL_CMAC */
#ifdef CONFIG_ECC
#include <openssl/ec.h>
#endif							/* CONFIG_ECC */

#include "common.h"
#include "wpabuf.h"
#include "dh_group5.h"
#include "sha1.h"
#include "sha256.h"
#include "sha384.h"
#include "crypto.h"

static BIGNUM *get_group5_prime(void)
{
#ifdef OPENSSL_IS_BORINGSSL
	static const unsigned char RFC3526_PRIME_1536[] = {
		0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2,
		0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
		0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6,
		0x3B, 0x13, 0x9B, 0x22, 0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
		0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 0x30, 0x2B, 0x0A, 0x6D,
		0xF2, 0x5F, 0x14, 0x37, 0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
		0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 0xF4, 0x4C, 0x42, 0xE9,
		0xA6, 0x37, 0xED, 0x6B, 0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
		0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11,
		0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D,
		0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 0x98, 0xDA, 0x48, 0x36,
		0x1C, 0x55, 0xD3, 0x9A, 0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F,
		0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 0x1C, 0x62, 0xF3, 0x56,
		0x20, 0x85, 0x52, 0xBB, 0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D,
		0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 0xF1, 0x74, 0x6C, 0x08,
		0xCA, 0x23, 0x73, 0x27, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
	};
	return BN_bin2bn(RFC3526_PRIME_1536, sizeof(RFC3526_PRIME_1536), NULL);
#else							/* OPENSSL_IS_BORINGSSL */
	return get_rfc3526_prime_1536(NULL);
#endif							/* OPENSSL_IS_BORINGSSL */
}

#ifdef OPENSSL_NO_SHA256
#define NO_SHA256_WRAPPER
#endif

static int openssl_digest_vector(const EVP_MD *type, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	EVP_MD_CTX ctx;
	size_t i;
	unsigned int mac_len;

	EVP_MD_CTX_init(&ctx);
	if (!EVP_DigestInit_ex(&ctx, type, NULL)) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_DigestInit_ex failed: %s", ERR_error_string(ERR_get_error(), NULL));
		return -1;
	}
	for (i = 0; i < num_elem; i++) {
		if (!EVP_DigestUpdate(&ctx, addr[i], len[i])) {
			wpa_printf(MSG_ERROR, "OpenSSL: EVP_DigestUpdate " "failed: %s", ERR_error_string(ERR_get_error(), NULL));
			return -1;
		}
	}
	if (!EVP_DigestFinal(&ctx, mac, &mac_len)) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_DigestFinal failed: %s", ERR_error_string(ERR_get_error(), NULL));
		return -1;
	}

	return 0;
}

int md4_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_digest_vector(EVP_md4(), num_elem, addr, len, mac);
}

void des_encrypt(const u8 *clear, const u8 *key, u8 *cypher)
{
	u8 pkey[8], next, tmp;
	int i;
	DES_key_schedule ks;

	/* Add parity bits to the key */
	next = 0;
	for (i = 0; i < 7; i++) {
		tmp = key[i];
		pkey[i] = (tmp >> i) | next | 1;
		next = tmp << (7 - i);
	}
	pkey[i] = next | 1;

	DES_set_key((DES_cblock *)&pkey, &ks);
	DES_ecb_encrypt((DES_cblock *)clear, (DES_cblock *)cypher, &ks, DES_ENCRYPT);
}

int rc4_skip(const u8 *key, size_t keylen, size_t skip, u8 *data, size_t data_len)
{
#ifdef OPENSSL_NO_RC4
	return -1;
#else							/* OPENSSL_NO_RC4 */
	EVP_CIPHER_CTX ctx;
	int outl;
	int res = -1;
	unsigned char skip_buf[16];

	EVP_CIPHER_CTX_init(&ctx);
	if (!EVP_CIPHER_CTX_set_padding(&ctx, 0) || !EVP_CipherInit_ex(&ctx, EVP_rc4(), NULL, NULL, NULL, 1) || !EVP_CIPHER_CTX_set_key_length(&ctx, keylen) || !EVP_CipherInit_ex(&ctx, NULL, NULL, key, NULL, 1)) {
		goto out;
	}

	while (skip >= sizeof(skip_buf)) {
		size_t len = skip;
		if (len > sizeof(skip_buf)) {
			len = sizeof(skip_buf);
		}
		if (!EVP_CipherUpdate(&ctx, skip_buf, &outl, skip_buf, len)) {
			goto out;
		}
		skip -= len;
	}

	if (EVP_CipherUpdate(&ctx, data, &outl, data, data_len)) {
		res = 0;
	}

out:
	EVP_CIPHER_CTX_cleanup(&ctx);
	return res;
#endif							/* OPENSSL_NO_RC4 */
}

int md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_digest_vector(EVP_md5(), num_elem, addr, len, mac);
}

int sha1_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_digest_vector(EVP_sha1(), num_elem, addr, len, mac);
}

#ifndef NO_SHA256_WRAPPER
int sha256_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_digest_vector(EVP_sha256(), num_elem, addr, len, mac);
}
#endif							/* NO_SHA256_WRAPPER */

static const EVP_CIPHER *aes_get_evp_cipher(size_t keylen)
{
	switch (keylen) {
	case 16:
		return EVP_aes_128_ecb();
#ifndef OPENSSL_IS_BORINGSSL
	case 24:
		return EVP_aes_192_ecb();
#endif							/* OPENSSL_IS_BORINGSSL */
	case 32:
		return EVP_aes_256_ecb();
	}

	return NULL;
}

void *aes_encrypt_init(const u8 *key, size_t len)
{
	EVP_CIPHER_CTX *ctx;
	const EVP_CIPHER *type;

	type = aes_get_evp_cipher(len);
	if (type == NULL) {
		return NULL;
	}

	ctx = os_malloc(sizeof(*ctx));
	if (ctx == NULL) {
		return NULL;
	}
	EVP_CIPHER_CTX_init(ctx);
	if (EVP_EncryptInit_ex(ctx, type, NULL, key, NULL) != 1) {
		os_free(ctx);
		return NULL;
	}
	EVP_CIPHER_CTX_set_padding(ctx, 0);
	return ctx;
}

void aes_encrypt(void *ctx, const u8 *plain, u8 *crypt)
{
	EVP_CIPHER_CTX *c = ctx;
	int clen = 16;
	if (EVP_EncryptUpdate(c, crypt, &clen, plain, 16) != 1) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_EncryptUpdate failed: %s", ERR_error_string(ERR_get_error(), NULL));
	}
}

void aes_encrypt_deinit(void *ctx)
{
	EVP_CIPHER_CTX *c = ctx;
	u8 buf[16];
	int len = sizeof(buf);
	if (EVP_EncryptFinal_ex(c, buf, &len) != 1) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_EncryptFinal_ex failed: " "%s", ERR_error_string(ERR_get_error(), NULL));
	}
	if (len != 0) {
		wpa_printf(MSG_ERROR, "OpenSSL: Unexpected padding length %d " "in AES encrypt", len);
	}
	EVP_CIPHER_CTX_cleanup(c);
	bin_clear_free(c, sizeof(*c));
}

void *aes_decrypt_init(const u8 *key, size_t len)
{
	EVP_CIPHER_CTX *ctx;
	const EVP_CIPHER *type;

	type = aes_get_evp_cipher(len);
	if (type == NULL) {
		return NULL;
	}

	ctx = os_malloc(sizeof(*ctx));
	if (ctx == NULL) {
		return NULL;
	}
	EVP_CIPHER_CTX_init(ctx);
	if (EVP_DecryptInit_ex(ctx, type, NULL, key, NULL) != 1) {
		os_free(ctx);
		return NULL;
	}
	EVP_CIPHER_CTX_set_padding(ctx, 0);
	return ctx;
}

void aes_decrypt(void *ctx, const u8 *crypt, u8 *plain)
{
	EVP_CIPHER_CTX *c = ctx;
	int plen = 16;
	if (EVP_DecryptUpdate(c, plain, &plen, crypt, 16) != 1) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_DecryptUpdate failed: %s", ERR_error_string(ERR_get_error(), NULL));
	}
}

void aes_decrypt_deinit(void *ctx)
{
	EVP_CIPHER_CTX *c = ctx;
	u8 buf[16];
	int len = sizeof(buf);
	if (EVP_DecryptFinal_ex(c, buf, &len) != 1) {
		wpa_printf(MSG_ERROR, "OpenSSL: EVP_DecryptFinal_ex failed: " "%s", ERR_error_string(ERR_get_error(), NULL));
	}
	if (len != 0) {
		wpa_printf(MSG_ERROR, "OpenSSL: Unexpected padding length %d " "in AES decrypt", len);
	}
	EVP_CIPHER_CTX_cleanup(c);
	bin_clear_free(c, sizeof(*c));
}

int aes_wrap(const u8 *kek, size_t kek_len, int n, const u8 *plain, u8 *cipher)
{
	AES_KEY actx;
	int res;

	if (AES_set_encrypt_key(kek, kek_len << 3, &actx)) {
		return -1;
	}
	res = AES_wrap_key(&actx, NULL, cipher, plain, n * 8);
	OPENSSL_cleanse(&actx, sizeof(actx));
	return res <= 0 ? -1 : 0;
}

int aes_unwrap(const u8 *kek, size_t kek_len, int n, const u8 *cipher, u8 *plain)
{
	AES_KEY actx;
	int res;

	if (AES_set_decrypt_key(kek, kek_len << 3, &actx)) {
		return -1;
	}
	res = AES_unwrap_key(&actx, NULL, plain, cipher, (n + 1) * 8);
	OPENSSL_cleanse(&actx, sizeof(actx));
	return res <= 0 ? -1 : 0;
}

int aes_128_cbc_encrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
{
	EVP_CIPHER_CTX ctx;
	int clen, len;
	u8 buf[16];

	EVP_CIPHER_CTX_init(&ctx);
	if (EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, key, iv) != 1) {
		return -1;
	}
	EVP_CIPHER_CTX_set_padding(&ctx, 0);

	clen = data_len;
	if (EVP_EncryptUpdate(&ctx, data, &clen, data, data_len) != 1 || clen != (int)data_len) {
		return -1;
	}

	len = sizeof(buf);
	if (EVP_EncryptFinal_ex(&ctx, buf, &len) != 1 || len != 0) {
		return -1;
	}
	EVP_CIPHER_CTX_cleanup(&ctx);

	return 0;
}

int aes_128_cbc_decrypt(const u8 *key, const u8 *iv, u8 *data, size_t data_len)
{
	EVP_CIPHER_CTX ctx;
	int plen, len;
	u8 buf[16];

	EVP_CIPHER_CTX_init(&ctx);
	if (EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, key, iv) != 1) {
		return -1;
	}
	EVP_CIPHER_CTX_set_padding(&ctx, 0);

	plen = data_len;
	if (EVP_DecryptUpdate(&ctx, data, &plen, data, data_len) != 1 || plen != (int)data_len) {
		return -1;
	}

	len = sizeof(buf);
	if (EVP_DecryptFinal_ex(&ctx, buf, &len) != 1 || len != 0) {
		return -1;
	}
	EVP_CIPHER_CTX_cleanup(&ctx);

	return 0;
}

int crypto_mod_exp(const u8 *base, size_t base_len, const u8 *power, size_t power_len, const u8 *modulus, size_t modulus_len, u8 *result, size_t *result_len)
{
	BIGNUM *bn_base, *bn_exp, *bn_modulus, *bn_result;
	int ret = -1;
	BN_CTX *ctx;

	ctx = BN_CTX_new();
	if (ctx == NULL) {
		return -1;
	}

	bn_base = BN_bin2bn(base, base_len, NULL);
	bn_exp = BN_bin2bn(power, power_len, NULL);
	bn_modulus = BN_bin2bn(modulus, modulus_len, NULL);
	bn_result = BN_new();

	if (bn_base == NULL || bn_exp == NULL || bn_modulus == NULL || bn_result == NULL) {
		goto error;
	}

	if (BN_mod_exp(bn_result, bn_base, bn_exp, bn_modulus, ctx) != 1) {
		goto error;
	}

	*result_len = BN_bn2bin(bn_result, result);
	ret = 0;

error:
	BN_clear_free(bn_base);
	BN_clear_free(bn_exp);
	BN_clear_free(bn_modulus);
	BN_clear_free(bn_result);
	BN_CTX_free(ctx);
	return ret;
}

struct crypto_cipher {
	EVP_CIPHER_CTX enc;
	EVP_CIPHER_CTX dec;
};

struct crypto_cipher *crypto_cipher_init(enum crypto_cipher_alg alg, const u8 *iv, const u8 *key, size_t key_len)
{
	struct crypto_cipher *ctx;
	const EVP_CIPHER *cipher;

	ctx = os_zalloc(sizeof(*ctx));
	if (ctx == NULL) {
		return NULL;
	}

	switch (alg) {
#ifndef OPENSSL_NO_RC4
	case CRYPTO_CIPHER_ALG_RC4:
		cipher = EVP_rc4();
		break;
#endif							/* OPENSSL_NO_RC4 */
#ifndef OPENSSL_NO_AES
	case CRYPTO_CIPHER_ALG_AES:
		switch (key_len) {
		case 16:
			cipher = EVP_aes_128_cbc();
			break;
#ifndef OPENSSL_IS_BORINGSSL
		case 24:
			cipher = EVP_aes_192_cbc();
			break;
#endif							/* OPENSSL_IS_BORINGSSL */
		case 32:
			cipher = EVP_aes_256_cbc();
			break;
		default:
			os_free(ctx);
			return NULL;
		}
		break;
#endif							/* OPENSSL_NO_AES */
#ifndef OPENSSL_NO_DES
	case CRYPTO_CIPHER_ALG_3DES:
		cipher = EVP_des_ede3_cbc();
		break;
	case CRYPTO_CIPHER_ALG_DES:
		cipher = EVP_des_cbc();
		break;
#endif							/* OPENSSL_NO_DES */
#ifndef OPENSSL_NO_RC2
	case CRYPTO_CIPHER_ALG_RC2:
		cipher = EVP_rc2_ecb();
		break;
#endif							/* OPENSSL_NO_RC2 */
	default:
		os_free(ctx);
		return NULL;
	}

	EVP_CIPHER_CTX_init(&ctx->enc);
	EVP_CIPHER_CTX_set_padding(&ctx->enc, 0);
	if (!EVP_EncryptInit_ex(&ctx->enc, cipher, NULL, NULL, NULL) || !EVP_CIPHER_CTX_set_key_length(&ctx->enc, key_len) || !EVP_EncryptInit_ex(&ctx->enc, NULL, NULL, key, iv)) {
		EVP_CIPHER_CTX_cleanup(&ctx->enc);
		os_free(ctx);
		return NULL;
	}

	EVP_CIPHER_CTX_init(&ctx->dec);
	EVP_CIPHER_CTX_set_padding(&ctx->dec, 0);
	if (!EVP_DecryptInit_ex(&ctx->dec, cipher, NULL, NULL, NULL) || !EVP_CIPHER_CTX_set_key_length(&ctx->dec, key_len) || !EVP_DecryptInit_ex(&ctx->dec, NULL, NULL, key, iv)) {
		EVP_CIPHER_CTX_cleanup(&ctx->enc);
		EVP_CIPHER_CTX_cleanup(&ctx->dec);
		os_free(ctx);
		return NULL;
	}

	return ctx;
}

int crypto_cipher_encrypt(struct crypto_cipher *ctx, const u8 *plain, u8 *crypt, size_t len)
{
	int outl;
	if (!EVP_EncryptUpdate(&ctx->enc, crypt, &outl, plain, len)) {
		return -1;
	}
	return 0;
}

int crypto_cipher_decrypt(struct crypto_cipher *ctx, const u8 *crypt, u8 *plain, size_t len)
{
	int outl;
	outl = len;
	if (!EVP_DecryptUpdate(&ctx->dec, plain, &outl, crypt, len)) {
		return -1;
	}
	return 0;
}

void crypto_cipher_deinit(struct crypto_cipher *ctx)
{
	EVP_CIPHER_CTX_cleanup(&ctx->enc);
	EVP_CIPHER_CTX_cleanup(&ctx->dec);
	os_free(ctx);
}

void *dh5_init(struct wpabuf **priv, struct wpabuf **publ)
{
	DH *dh;
	struct wpabuf *pubkey = NULL, *privkey = NULL;
	size_t publen, privlen;

	*priv = NULL;
	*publ = NULL;

	dh = DH_new();
	if (dh == NULL) {
		return NULL;
	}

	dh->g = BN_new();
	if (dh->g == NULL || BN_set_word(dh->g, 2) != 1) {
		goto err;
	}

	dh->p = get_group5_prime();
	if (dh->p == NULL) {
		goto err;
	}

	if (DH_generate_key(dh) != 1) {
		goto err;
	}

	publen = BN_num_bytes(dh->pub_key);
	pubkey = wpabuf_alloc(publen);
	if (pubkey == NULL) {
		goto err;
	}
	privlen = BN_num_bytes(dh->priv_key);
	privkey = wpabuf_alloc(privlen);
	if (privkey == NULL) {
		goto err;
	}

	BN_bn2bin(dh->pub_key, wpabuf_put(pubkey, publen));
	BN_bn2bin(dh->priv_key, wpabuf_put(privkey, privlen));

	*priv = privkey;
	*publ = pubkey;
	return dh;

err:
	wpabuf_clear_free(pubkey);
	wpabuf_clear_free(privkey);
	DH_free(dh);
	return NULL;
}

void *dh5_init_fixed(const struct wpabuf *priv, const struct wpabuf *publ)
{
	DH *dh;

	dh = DH_new();
	if (dh == NULL) {
		return NULL;
	}

	dh->g = BN_new();
	if (dh->g == NULL || BN_set_word(dh->g, 2) != 1) {
		goto err;
	}

	dh->p = get_group5_prime();
	if (dh->p == NULL) {
		goto err;
	}

	dh->priv_key = BN_bin2bn(wpabuf_head(priv), wpabuf_len(priv), NULL);
	if (dh->priv_key == NULL) {
		goto err;
	}

	dh->pub_key = BN_bin2bn(wpabuf_head(publ), wpabuf_len(publ), NULL);
	if (dh->pub_key == NULL) {
		goto err;
	}

	if (DH_generate_key(dh) != 1) {
		goto err;
	}

	return dh;

err:
	DH_free(dh);
	return NULL;
}

struct wpabuf *dh5_derive_shared(void *ctx, const struct wpabuf *peer_public, const struct wpabuf *own_private)
{
	BIGNUM *pub_key;
	struct wpabuf *res = NULL;
	size_t rlen;
	DH *dh = ctx;
	int keylen;

	if (ctx == NULL) {
		return NULL;
	}

	pub_key = BN_bin2bn(wpabuf_head(peer_public), wpabuf_len(peer_public), NULL);
	if (pub_key == NULL) {
		return NULL;
	}

	rlen = DH_size(dh);
	res = wpabuf_alloc(rlen);
	if (res == NULL) {
		goto err;
	}

	keylen = DH_compute_key(wpabuf_mhead(res), pub_key, dh);
	if (keylen < 0) {
		goto err;
	}
	wpabuf_put(res, keylen);
	BN_clear_free(pub_key);

	return res;

err:
	BN_clear_free(pub_key);
	wpabuf_clear_free(res);
	return NULL;
}

void dh5_free(void *ctx)
{
	DH *dh;
	if (ctx == NULL) {
		return;
	}
	dh = ctx;
	DH_free(dh);
}

struct crypto_hash {
	HMAC_CTX ctx;
};

struct crypto_hash *crypto_hash_init(enum crypto_hash_alg alg, const u8 *key, size_t key_len)
{
	struct crypto_hash *ctx;
	const EVP_MD *md;

	switch (alg) {
#ifndef OPENSSL_NO_MD5
	case CRYPTO_HASH_ALG_HMAC_MD5:
		md = EVP_md5();
		break;
#endif							/* OPENSSL_NO_MD5 */
#ifndef OPENSSL_NO_SHA
	case CRYPTO_HASH_ALG_HMAC_SHA1:
		md = EVP_sha1();
		break;
#endif							/* OPENSSL_NO_SHA */
#ifndef OPENSSL_NO_SHA256
#ifdef CONFIG_SHA256
	case CRYPTO_HASH_ALG_HMAC_SHA256:
		md = EVP_sha256();
		break;
#endif							/* CONFIG_SHA256 */
#endif							/* OPENSSL_NO_SHA256 */
	default:
		return NULL;
	}

	ctx = os_zalloc(sizeof(*ctx));
	if (ctx == NULL) {
		return NULL;
	}
	HMAC_CTX_init(&ctx->ctx);

#if OPENSSL_VERSION_NUMBER < 0x00909000
	HMAC_Init_ex(&ctx->ctx, key, key_len, md, NULL);
#else							/* openssl < 0.9.9 */
	if (HMAC_Init_ex(&ctx->ctx, key, key_len, md, NULL) != 1) {
		bin_clear_free(ctx, sizeof(*ctx));
		return NULL;
	}
#endif							/* openssl < 0.9.9 */

	return ctx;
}

void crypto_hash_update(struct crypto_hash *ctx, const u8 *data, size_t len)
{
	if (ctx == NULL) {
		return;
	}
	HMAC_Update(&ctx->ctx, data, len);
}

int crypto_hash_finish(struct crypto_hash *ctx, u8 *mac, size_t *len)
{
	unsigned int mdlen;
	int res;

	if (ctx == NULL) {
		return -2;
	}

	if (mac == NULL || len == NULL) {
		bin_clear_free(ctx, sizeof(*ctx));
		return 0;
	}

	mdlen = *len;
#if OPENSSL_VERSION_NUMBER < 0x00909000
	HMAC_Final(&ctx->ctx, mac, &mdlen);
	res = 1;
#else							/* openssl < 0.9.9 */
	res = HMAC_Final(&ctx->ctx, mac, &mdlen);
#endif							/* openssl < 0.9.9 */
	HMAC_CTX_cleanup(&ctx->ctx);
	bin_clear_free(ctx, sizeof(*ctx));

	if (res == 1) {
		*len = mdlen;
		return 0;
	}

	return -1;
}

static int openssl_hmac_vector(const EVP_MD *type, const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac, unsigned int mdlen)
{
	HMAC_CTX ctx;
	size_t i;
	int res;

	HMAC_CTX_init(&ctx);
#if OPENSSL_VERSION_NUMBER < 0x00909000
	HMAC_Init_ex(&ctx, key, key_len, type, NULL);
#else							/* openssl < 0.9.9 */
	if (HMAC_Init_ex(&ctx, key, key_len, type, NULL) != 1) {
		return -1;
	}
#endif							/* openssl < 0.9.9 */

	for (i = 0; i < num_elem; i++) {
		HMAC_Update(&ctx, addr[i], len[i]);
	}

#if OPENSSL_VERSION_NUMBER < 0x00909000
	HMAC_Final(&ctx, mac, &mdlen);
	res = 1;
#else							/* openssl < 0.9.9 */
	res = HMAC_Final(&ctx, mac, &mdlen);
#endif							/* openssl < 0.9.9 */
	HMAC_CTX_cleanup(&ctx);

	return res == 1 ? 0 : -1;
}

#ifndef CONFIG_FIPS

int hmac_md5_vector(const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_hmac_vector(EVP_md5(), key, key_len, num_elem, addr, len, mac, 16);
}

int hmac_md5(const u8 *key, size_t key_len, const u8 *data, size_t data_len, u8 *mac)
{
	return hmac_md5_vector(key, key_len, 1, &data, &data_len, mac);
}

#endif							/* CONFIG_FIPS */

int pbkdf2_sha1(const char *passphrase, const u8 *ssid, size_t ssid_len, int iterations, u8 *buf, size_t buflen)
{
	if (PKCS5_PBKDF2_HMAC_SHA1(passphrase, os_strlen(passphrase), ssid, ssid_len, iterations, buflen, buf) != 1) {
		return -1;
	}
	return 0;
}

int hmac_sha1_vector(const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_hmac_vector(EVP_sha1(), key, key_len, num_elem, addr, len, mac, 20);
}

int hmac_sha1(const u8 *key, size_t key_len, const u8 *data, size_t data_len, u8 *mac)
{
	return hmac_sha1_vector(key, key_len, 1, &data, &data_len, mac);
}

#ifdef CONFIG_SHA256

int hmac_sha256_vector(const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_hmac_vector(EVP_sha256(), key, key_len, num_elem, addr, len, mac, 32);
}

int hmac_sha256(const u8 *key, size_t key_len, const u8 *data, size_t data_len, u8 *mac)
{
	return hmac_sha256_vector(key, key_len, 1, &data, &data_len, mac);
}

#endif							/* CONFIG_SHA256 */

#ifdef CONFIG_SHA384

int hmac_sha384_vector(const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return openssl_hmac_vector(EVP_sha384(), key, key_len, num_elem, addr, len, mac, 32);
}

int hmac_sha384(const u8 *key, size_t key_len, const u8 *data, size_t data_len, u8 *mac)
{
	return hmac_sha384_vector(key, key_len, 1, &data, &data_len, mac);
}

#endif							/* CONFIG_SHA384 */

int crypto_get_random(void *buf, size_t len)
{
	if (RAND_bytes(buf, len) != 1) {
		return -1;
	}
	return 0;
}

#ifdef CONFIG_OPENSSL_CMAC
int omac1_aes_vector(const u8 *key, size_t key_len, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	CMAC_CTX *ctx;
	int ret = -1;
	size_t outlen, i;

	ctx = CMAC_CTX_new();
	if (ctx == NULL) {
		return -1;
	}

	if (key_len == 32) {
		if (!CMAC_Init(ctx, key, 32, EVP_aes_256_cbc(), NULL)) {
			goto fail;
		}
	} else if (key_len == 16) {
		if (!CMAC_Init(ctx, key, 16, EVP_aes_128_cbc(), NULL)) {
			goto fail;
		}
	} else {
		goto fail;
	}
	for (i = 0; i < num_elem; i++) {
		if (!CMAC_Update(ctx, addr[i], len[i])) {
			goto fail;
		}
	}
	if (!CMAC_Final(ctx, mac, &outlen) || outlen != 16) {
		goto fail;
	}

	ret = 0;
fail:
	CMAC_CTX_free(ctx);
	return ret;
}

int omac1_aes_128_vector(const u8 *key, size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
	return omac1_aes_vector(key, 16, num_elem, addr, len, mac);
}

int omac1_aes_128(const u8 *key, const u8 *data, size_t data_len, u8 *mac)
{
	return omac1_aes_128_vector(key, 1, &data, &data_len, mac);
}

int omac1_aes_256(const u8 *key, const u8 *data, size_t data_len, u8 *mac)
{
	return omac1_aes_vector(key, 32, 1, &data, &data_len, mac);
}
#endif							/* CONFIG_OPENSSL_CMAC */

struct crypto_bignum *crypto_bignum_init(void)
{
	return (struct crypto_bignum *)BN_new();
}

struct crypto_bignum *crypto_bignum_init_set(const u8 *buf, size_t len)
{
	BIGNUM *bn = BN_bin2bn(buf, len, NULL);
	return (struct crypto_bignum *)bn;
}

void crypto_bignum_deinit(struct crypto_bignum *n, int clear)
{
	if (clear) {
		BN_clear_free((BIGNUM *)n);
	} else {
		BN_free((BIGNUM *)n);
	}
}

int crypto_bignum_to_bin(const struct crypto_bignum *a, u8 *buf, size_t buflen, size_t padlen)
{
	int num_bytes, offset;

	if (padlen > buflen) {
		return -1;
	}

	num_bytes = BN_num_bytes((const BIGNUM *)a);
	if ((size_t)num_bytes > buflen) {
		return -1;
	}
	if (padlen > (size_t)num_bytes) {
		offset = padlen - num_bytes;
	} else {
		offset = 0;
	}

	os_memset(buf, 0, offset);
	BN_bn2bin((const BIGNUM *)a, buf + offset);

	return num_bytes + offset;
}

int crypto_bignum_add(const struct crypto_bignum *a, const struct crypto_bignum *b, struct crypto_bignum *c)
{
	return BN_add((BIGNUM *)c, (const BIGNUM *)a, (const BIGNUM *)b) ? 0 : -1;
}

int crypto_bignum_mod(const struct crypto_bignum *a, const struct crypto_bignum *b, struct crypto_bignum *c)
{
	int res;
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -1;
	}
	res = BN_mod((BIGNUM *)c, (const BIGNUM *)a, (const BIGNUM *)b, bnctx);
	BN_CTX_free(bnctx);

	return res ? 0 : -1;
}

int crypto_bignum_exptmod(const struct crypto_bignum *a, const struct crypto_bignum *b, const struct crypto_bignum *c, struct crypto_bignum *d)
{
	int res;
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -1;
	}
	res = BN_mod_exp((BIGNUM *)d, (const BIGNUM *)a, (const BIGNUM *)b, (const BIGNUM *)c, bnctx);
	BN_CTX_free(bnctx);

	return res ? 0 : -1;
}

int crypto_bignum_inverse(const struct crypto_bignum *a, const struct crypto_bignum *b, struct crypto_bignum *c)
{
	BIGNUM *res;
	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -1;
	}
	res = BN_mod_inverse((BIGNUM *)c, (const BIGNUM *)a, (const BIGNUM *)b, bnctx);
	BN_CTX_free(bnctx);

	return res ? 0 : -1;
}

int crypto_bignum_sub(const struct crypto_bignum *a, const struct crypto_bignum *b, struct crypto_bignum *c)
{
	return BN_sub((BIGNUM *)c, (const BIGNUM *)a, (const BIGNUM *)b) ? 0 : -1;
}

int crypto_bignum_div(const struct crypto_bignum *a, const struct crypto_bignum *b, struct crypto_bignum *c)
{
	int res;

	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -1;
	}
	res = BN_div((BIGNUM *)c, NULL, (const BIGNUM *)a, (const BIGNUM *)b, bnctx);
	BN_CTX_free(bnctx);

	return res ? 0 : -1;
}

int crypto_bignum_mulmod(const struct crypto_bignum *a, const struct crypto_bignum *b, const struct crypto_bignum *c, struct crypto_bignum *d)
{
	int res;

	BN_CTX *bnctx;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -1;
	}
	res = BN_mod_mul((BIGNUM *)d, (const BIGNUM *)a, (const BIGNUM *)b, (const BIGNUM *)c, bnctx);
	BN_CTX_free(bnctx);

	return res ? 0 : -1;
}

int crypto_bignum_cmp(const struct crypto_bignum *a, const struct crypto_bignum *b)
{
	return BN_cmp((const BIGNUM *)a, (const BIGNUM *)b);
}

int crypto_bignum_bits(const struct crypto_bignum *a)
{
	return BN_num_bits((const BIGNUM *)a);
}

int crypto_bignum_is_zero(const struct crypto_bignum *a)
{
	return BN_is_zero((const BIGNUM *)a);
}

int crypto_bignum_is_one(const struct crypto_bignum *a)
{
	return BN_is_one((const BIGNUM *)a);
}

int crypto_bignum_legendre(const struct crypto_bignum *a, const struct crypto_bignum *p)
{
	BN_CTX *bnctx;
	BIGNUM *exp = NULL, *tmp = NULL;
	int res = -2;

	bnctx = BN_CTX_new();
	if (bnctx == NULL) {
		return -2;
	}

	exp = BN_new();
	tmp = BN_new();
	if (!exp || !tmp ||
		/* exp = (p-1) / 2 */
		!BN_sub(exp, (const BIGNUM *)p, BN_value_one()) || !BN_rshift1(exp, exp) || !BN_mod_exp(tmp, (const BIGNUM *)a, exp, (const BIGNUM *)p, bnctx)) {
		goto fail;
	}

	if (BN_is_word(tmp, 1)) {
		res = 1;
	} else if (BN_is_zero(tmp)) {
		res = 0;
	} else {
		res = -1;
	}

fail:
	BN_clear_free(tmp);
	BN_clear_free(exp);
	BN_CTX_free(bnctx);
	return res;
}

#ifdef CONFIG_ECC

struct crypto_ec {
	EC_GROUP *group;
	BN_CTX *bnctx;
	BIGNUM *prime;
	BIGNUM *order;
	BIGNUM *a;
	BIGNUM *b;
};

struct crypto_ec *crypto_ec_init(int group)
{
	struct crypto_ec *e;
	int nid;

	/* Map from IANA registry for IKE D-H groups to OpenSSL NID */
	switch (group) {
	case 19:
		nid = NID_X9_62_prime256v1;
		break;
	case 20:
		nid = NID_secp384r1;
		break;
	case 21:
		nid = NID_secp521r1;
		break;
	case 25:
		nid = NID_X9_62_prime192v1;
		break;
	case 26:
		nid = NID_secp224r1;
		break;
#ifdef NID_brainpoolP224r1
	case 27:
		nid = NID_brainpoolP224r1;
		break;
#endif							/* NID_brainpoolP224r1 */
#ifdef NID_brainpoolP256r1
	case 28:
		nid = NID_brainpoolP256r1;
		break;
#endif							/* NID_brainpoolP256r1 */
#ifdef NID_brainpoolP384r1
	case 29:
		nid = NID_brainpoolP384r1;
		break;
#endif							/* NID_brainpoolP384r1 */
#ifdef NID_brainpoolP512r1
	case 30:
		nid = NID_brainpoolP512r1;
		break;
#endif							/* NID_brainpoolP512r1 */
	default:
		return NULL;
	}

	e = os_zalloc(sizeof(*e));
	if (e == NULL) {
		return NULL;
	}

	e->bnctx = BN_CTX_new();
	e->group = EC_GROUP_new_by_curve_name(nid);
	e->prime = BN_new();
	e->order = BN_new();
	e->a = BN_new();
	e->b = BN_new();
	if (e->group == NULL || e->bnctx == NULL || e->prime == NULL || e->order == NULL || e->a == NULL || e->b == NULL || !EC_GROUP_get_curve_GFp(e->group, e->prime, e->a, e->b, e->bnctx) || !EC_GROUP_get_order(e->group, e->order, e->bnctx)) {
		crypto_ec_deinit(e);
		e = NULL;
	}

	return e;
}

void crypto_ec_deinit(struct crypto_ec *e)
{
	if (e == NULL) {
		return;
	}
	BN_clear_free(e->b);
	BN_clear_free(e->a);
	BN_clear_free(e->order);
	BN_clear_free(e->prime);
	EC_GROUP_free(e->group);
	BN_CTX_free(e->bnctx);
	os_free(e);
}

struct crypto_ec_point *crypto_ec_point_init(struct crypto_ec *e)
{
	if (e == NULL) {
		return NULL;
	}
	return (struct crypto_ec_point *)EC_POINT_new(e->group);
}

size_t crypto_ec_prime_len(struct crypto_ec *e)
{
	return BN_num_bytes(e->prime);
}

size_t crypto_ec_prime_len_bits(struct crypto_ec *e)
{
	return BN_num_bits(e->prime);
}

const struct crypto_bignum *crypto_ec_get_prime(struct crypto_ec *e)
{
	return (const struct crypto_bignum *)e->prime;
}

const struct crypto_bignum *crypto_ec_get_order(struct crypto_ec *e)
{
	return (const struct crypto_bignum *)e->order;
}

void crypto_ec_point_deinit(struct crypto_ec_point *p, int clear)
{
	if (clear) {
		EC_POINT_clear_free((EC_POINT *)p);
	} else {
		EC_POINT_free((EC_POINT *)p);
	}
}

int crypto_ec_point_to_bin(struct crypto_ec *e, const struct crypto_ec_point *point, u8 *x, u8 *y)
{
	BIGNUM *x_bn, *y_bn;
	int ret = -1;
	int len = BN_num_bytes(e->prime);

	x_bn = BN_new();
	y_bn = BN_new();

	if (x_bn && y_bn && EC_POINT_get_affine_coordinates_GFp(e->group, (EC_POINT *)point, x_bn, y_bn, e->bnctx)) {
		if (x) {
			crypto_bignum_to_bin((struct crypto_bignum *)x_bn, x, len, len);
		}
		if (y) {
			crypto_bignum_to_bin((struct crypto_bignum *)y_bn, y, len, len);
		}
		ret = 0;
	}

	BN_clear_free(x_bn);
	BN_clear_free(y_bn);
	return ret;
}

struct crypto_ec_point *crypto_ec_point_from_bin(struct crypto_ec *e, const u8 *val)
{
	BIGNUM *x, *y;
	EC_POINT *elem;
	int len = BN_num_bytes(e->prime);

	x = BN_bin2bn(val, len, NULL);
	y = BN_bin2bn(val + len, len, NULL);
	elem = EC_POINT_new(e->group);
	if (x == NULL || y == NULL || elem == NULL) {
		BN_clear_free(x);
		BN_clear_free(y);
		EC_POINT_clear_free(elem);
		return NULL;
	}

	if (!EC_POINT_set_affine_coordinates_GFp(e->group, elem, x, y, e->bnctx)) {
		EC_POINT_clear_free(elem);
		elem = NULL;
	}

	BN_clear_free(x);
	BN_clear_free(y);

	return (struct crypto_ec_point *)elem;
}

int crypto_ec_point_add(struct crypto_ec *e, const struct crypto_ec_point *a, const struct crypto_ec_point *b, struct crypto_ec_point *c)
{
	return EC_POINT_add(e->group, (EC_POINT *)c, (const EC_POINT *)a, (const EC_POINT *)b, e->bnctx) ? 0 : -1;
}

int crypto_ec_point_mul(struct crypto_ec *e, const struct crypto_ec_point *p, const struct crypto_bignum *b, struct crypto_ec_point *res)
{
	return EC_POINT_mul(e->group, (EC_POINT *)res, NULL, (const EC_POINT *)p, (const BIGNUM *)b, e->bnctx)
		   ? 0 : -1;
}

int crypto_ec_point_invert(struct crypto_ec *e, struct crypto_ec_point *p)
{
	return EC_POINT_invert(e->group, (EC_POINT *)p, e->bnctx) ? 0 : -1;
}

int crypto_ec_point_solve_y_coord(struct crypto_ec *e, struct crypto_ec_point *p, const struct crypto_bignum *x, int y_bit)
{
	if (!EC_POINT_set_compressed_coordinates_GFp(e->group, (EC_POINT *)p, (const BIGNUM *)x, y_bit, e->bnctx) || !EC_POINT_is_on_curve(e->group, (EC_POINT *)p, e->bnctx)) {
		return -1;
	}
	return 0;
}

struct crypto_bignum *crypto_ec_point_compute_y_sqr(struct crypto_ec *e, const struct crypto_bignum *x)
{
	BIGNUM *tmp, *tmp2, *y_sqr = NULL;

	tmp = BN_new();
	tmp2 = BN_new();

	/* y^2 = x^3 + ax + b */
	if (tmp && tmp2 && BN_mod_sqr(tmp, (const BIGNUM *)x, e->prime, e->bnctx) && BN_mod_mul(tmp, tmp, (const BIGNUM *)x, e->prime, e->bnctx) && BN_mod_mul(tmp2, e->a, (const BIGNUM *)x, e->prime, e->bnctx) && BN_mod_add_quick(tmp2, tmp2, tmp, e->prime) && BN_mod_add_quick(tmp2, tmp2, e->b, e->prime)) {
		y_sqr = tmp2;
		tmp2 = NULL;
	}

	BN_clear_free(tmp);
	BN_clear_free(tmp2);

	return (struct crypto_bignum *)y_sqr;
}

int crypto_ec_point_is_at_infinity(struct crypto_ec *e, const struct crypto_ec_point *p)
{
	return EC_POINT_is_at_infinity(e->group, (const EC_POINT *)p);
}

int crypto_ec_point_is_on_curve(struct crypto_ec *e, const struct crypto_ec_point *p)
{
	return EC_POINT_is_on_curve(e->group, (const EC_POINT *)p, e->bnctx) == 1;
}

int crypto_ec_point_cmp(const struct crypto_ec *e, const struct crypto_ec_point *a, const struct crypto_ec_point *b)
{
	return EC_POINT_cmp(e->group, (const EC_POINT *)a, (const EC_POINT *)b, e->bnctx);
}

#endif							/* CONFIG_ECC */
